A spring seat includes a receiving part for receiving the end portion of a coil spring, and prevents the generation of noise and the abrasion of a suspension arm and the coil spring caused by the direct contact of the coil spring with the suspension arm.
In the case in which the suspension arm on which the spring seat is mounted is made of steel, the spring seat can be provided easily on the suspension arm by molding a mounting part of a spring seat for positioning and holding the spring seat by press molding or by weldedly fixing a bracket provided with the receiving part to the suspension arm.
Unfortunately, a structure in which the suspension arm is formed of an extruded material of aluminum has a problem of having difficulty in employing the above-described manufacturing means. For this reason, a bracket provided with the receiving part must be fasteningly fixed to the suspension arm with attaching bolts or the like, so that the mounting of the bracket to the suspension arm takes much time and labor, and the mounting workability is deteriorated.
As a technique for solving this problem, conventionally, as disclosed in sections [0024] to [0027] in the specification and FIG. 3 of the drawings of Patent Document 1 (Japanese Patent No. 3522130), there has been applicable a technique in which a spring seat body provided with the receiving part for receiving the coil spring and a locking protrusion, which projects from the spring seat body to the side opposite to the receiving part and is insertedly locked in a locking hole formed in the suspension arm are formed integrally using an elastic member.
According to the technique of Patent Document 1, since the locking protrusion is formed by the elastic member, the locking protrusion subjected to loads in the up and down direction and in the radial direction of the spring seat when the vehicle is running deforms greatly. Therefore, the position and posture of the spring seat becomes unstable, and additionally the durability of locking protrusion is decreased.